How do stars like Sarah Jessica Parker, Kelly Ripa, and Shakira get those toned bodies? Fitness trainer Anna Kaiser is the secret weapon superstars like these rely on to stay in tip-top shape.

With summer fast-approaching (bathing suit season!), "Good Morning America" asked the celebrity trainer to give us her top tips to get the best beach body possible in one week, and had two real women put it to the test.

Kaiser's Skinny Summer Workout Tips

• Try eating five 300-calorie meals per day. Instead of three big meals, you keep your energy consistent throughout the day this way, Kaiser said. "You keep your metabolism burning and you keep yourself from getting too hungry ."
• Cut out sugar, including artificial sweeteners and alcohol. "Sugar acts as a toxin in your body," Kaiser explained. The "faster you can cut it out and start nourishing your body with real food, the better you are going to feel. "
• Sleep 8 hours each night. Getting in shape is not only about diet and exercise. "The more tired you are, the hungrier you are going to be the next day," she said.
• Drink at least 64 ounces of water per day.
• Ten-minute cardio-interval workout, once or twice a day. Kaiser suggests doing an interval routine combining 30 seconds of cardio - a skater move that's the cornerstone of the workout - followed by a strengthening move to make sure you get the most efficient workout possible. Click here to see more of Kaiser's workouts. Cardio Skater Move (30 seconds) Strengthening Arms: Windshield wipers (x20) Cardio Skater Move (30 seconds) Strengthening Abs: Kickstand (x10 each side) Cardio Skater Move (30 seconds) Strengthening Legs: Curtsy jump (x10 each side) Cardio Skater Move (30 seconds)
• Stop eating three hours before bedtime.

Anna Kaiser's Top Workout Tips, Plus Habits You Should Avoid

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